More than 13 months ago, I wrote a column that began: “Sarah Palin can be the Republican nominee in 2012. I am not saying she will be, but she can be. Those who underestimate her do so at their own risk.” It was not the most popular column I ever wrote. I remember snickering and mockery from those who could not find actual vegetables to throw. After all, as was widely believed at the time, Sarah Palin was an idiot. Her interview with CBS’s Katie Couric had proved that. And Palin’s approval rating as governor of Alaska, once so high,...